This thing can emulate:
GPEngine: PCEngine Emulator beta 2
Frodo: Commodore64 Emulator
Craigs 8080 Arcade Emu v1.0 (MAME)
MSX1/MSX2 Emulator
NeoGeo Pocket emulator
InfoNES GP32 v.3 Emulator
Snes9xGP ver 0.8
+ more

http://www.lik-sang.com/info.php?category=126&products_id=812&#accessories

A friend of mine has got one. The device is brilliant but using it you have to be a techie otherwise you'll never understand it or get it working properly...

He bought it not too long ago when I sent him the link to the device, I don't think he's ever actually used it much though...